#include<glut.h>

void display(void)
{
	glClear(GL_COLOR_BUFFER_BIT);
	glColor3f(1.0,1.0,1.0);

	glBegin(GL_POLYGON);
	glVertex3f(0.25,0.25,0.0);
	glVertex3f(0.75,0.25,0.0);
	glVertex3f(0.75,0.75,0.0);
	glVertex3f(0.25,0.75,0.0);
	glEnd();
	glFlush();
}

void init(void)
{
	glClearColor(0.0,0.0,0.0,0.0);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(0.0,1.0,0.0,1.0,-1.0,1.0);
}

int main(int argc,char** argv)
{
	glutInit(&argc,argv);
	glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);
	glutInitWindowSize(300,300);
	glutInitWindowPosition(10,10);
	glutCreateWindow("init");
	init();
	glutDisplayFunc(display);
	glutMainLoop();
	return 0;
}